Rationale:

This research study is testing a study vaccine (mRNA-1647) that is being developed for preventing cytomegalovirus (CMV) infection. CMV is a common virus that can spread easily through an infected person’s saliva, blood, urine and breast milk. It is unusual for a CMV infection in a healthy person to cause illness and when it does symptoms are relatively mild. However, if a pregnant woman has a CMV infection, it may be passed to her unborn child. Children born with CMV can suffer long-term disability due to birth defects, including hearing loss or even death in very severe cases. CMV is the leading cause of birth defects around the world. There is currently no approved vaccine to prevent CMV infection.

Eligibility: 

• Healthy females aged 18 – 40- If more than 20 years old, must have regular contact with small children- Not currently pregnant or planning on becoming pregnant within the next 9 months